Chloe West was stabbed nine times in the face and upper body. Photograph: Caters News Agency

A 14-year-old girl was airlifted to hospital after she was stabbed by a man outside a secondary school.

Chloe West suffered nine knife wounds to her upper body and face outside Ridgewood high school in Wollaston, Stourbridge, according to police in Dudley, West Midlands. Officers said her injuries were serious but that she was in a stable condition last night.

Teachers, parents and other students are believed to have subdued and sat on her attacker until police arrived.

An 18-year-old man was arrested. Police said the suspect was known to Chloe.

It was alleged that the attacker was angry because his text messages had not been returned.

The 14-year-old was airlifted to Birmingham children's hospital, north of Stourbridge, after the attack, which happened at around 8.40am.

The school was shut for the day while police investigated. A Volkswagen Golf believed to have been used by the attacker was removed from the scene.

Chloe's parents, Rosemary and Nigel West, are distraught, according to neighbours.

Praising the quick-thinking teachers, parents and students who sat on the attacker, Superintendent Stuart Johnson from West Midlands police said: "I would just like to pay tribute to the very brave individuals who, without too much thought for their own safety, intervened at the time of the incident this morning.

"They showed tremendous bravery in intervening and actually detaining the suspect. In my opinion, based on medical evidence, they clearly prevented far more serious injuries to Chloe."

Officers were at the scene within minutes of the stabbing by the main gates. Johnson said: "On arrival, they saw that there was indeed a young lady, who we since know to be a pupil at the school, with serious injuries, believed to be knife wounds.

"They also found that a young man, who we have since established does not attend the school, had been detained by members of the public here in the street."

Johnson said the injuries to Chloe's upper body and face were no longer life threatening and that she was conscious.

Wollaston councillor Margaret Cowell, who lives nearby, said: "I've lived here 50 years and in all that time I've never heard a police car go up with its sirens on."

Ridgewood's head, Clive Nutting, said: "Police were called to the school today before 8.50am after one of the pupils was attacked on their way to school."